| 1. |
- Díaz-Álvarez, Alba E., et al.
(författare)
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Access to Optically Pure beta-Hydroxy Esters via Non-Enzymatic Kinetic Resolution by a Planar-Chiral DMAP Catalyst
- 2014
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 19:9, s. 14273-14291
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Tidskriftsartikel (refereegranskat)abstract
- The development of new approaches to obtain optically pure beta-hydroxy esters is an important area in synthetic organic chemistry since they are precursors of other high value compounds. Herein, the kinetic resolution of racemic beta-hydroxy esters using a planar-chiral DMAP derivative catalyst is presented. Following this procedure, a range of aromatic beta-hydroxy esters was obtained in excellent selectivities (up to s = 107) and high enantiomeric excess (up to 99% ee). Furthermore, the utility of the present method was demonstrated in the synthesis of (S)-3-hydroxy-N-methyl-3-phenylpropanamide, a key intermediate for bioactive molecules such as fluoxetine, tomoxetine or nisoxetine, in its enantiomerically pure form.
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| 2. |
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| 3. |
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| 4. |
- Mesas-Sánchez, Laura, 1985-, et al.
(författare)
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A Mechanistic Investigation of the Kinetic Resolution of Secondary Aromatic Alcohols Using a Ferrocene-Based Planar Chiral 4-(Dimethylamino)pyridine Catalyst
- 2015
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Ingår i: Chemistry - A European Journal. - : Wiley-VCH Verlagsgesellschaft. - 0947-6539 .- 1521-3765. ; 21:14, s. 5623-5631
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Tidskriftsartikel (refereegranskat)abstract
- A detailed computational and kinetic analysis of the acetylation of 1-phenylethanol with acetic anhydride catalyzed by planar chiral 4-(dimethylamino) pyridine (DMAP) catalyst ( )-1 is presented. The study includes a computational investigation of the potential-energy surface including the acylation and stereoselective transition states at the DFT level of theory. Experimentally, the kinetic study shows that the reaction proceeds in a first-order manner in catalyst, whereas both substrates, acetic anhydride and 1-phenylethanol, show fractional order, which is in accordance with steady-state conditions. The fractional order depends on an equilibrium between the free catalyst and the acetylated catalyst.
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| 5. |
- Mesas-Sanchez, Laura, et al.
(författare)
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Kinetic resolution of 2-hydroxy-2-aryl-ethylphosphonates by a non-enzymatic acylation catalyst
- 2014
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Ingår i: Tetrahedron. - : Elsevier. - 0040-4020 .- 1464-5416. ; 70:24, s. 3807-3811
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Tidskriftsartikel (refereegranskat)abstract
- Optically pure hydroxyphosphonates are widely used as derivatizable compounds that can be incorporated into a variety of synthetic strategies for the preparation of other high value organic products. A non-enzymatic kinetic resolution procedure to obtain chiral 2-hydroxy-2-arylethylphosphonates from the easily available racemic counterparts is described. A range of 2-hydroxy-2-arylethylphosphonates was efficiently resolved employing a planar-chiral DMAP derived catalyst with good selectivities (up to S=68). The chiral hydroxyphosphonates were isolated in good yields and high enantiomeric excess (>94% ee).
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| 6. |
- Mesas-Sánchez, Laura, et al.
(författare)
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Non-enzymatic kinetic resolution of 1,2-azidoalcohols using a planar-chiral DMAP derivative catalyst
- 2013
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Ingår i: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 69:2, s. 753-757
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Tidskriftsartikel (refereegranskat)abstract
- Optically pure 1,2-azidoalcohols are widely used as precursors for other high value organic products. A non-enzymatic kinetic resolution procedure for the stereoselective synthesis of chiral 1,2-azidoalcohols from the readily available racemic counterparts has been developed, employing a planar-chiral DMAP derivative catalyst. Following this procedure, a range of aromatic 1,2-azidoalcohols was obtained in good selectivities (up to S=45) and high enantiomeric excess (up to 99% ee).
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| 7. |
- Mesas Sánchez, Laura, 1985-
(författare)
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Organocatalytic Acylation for the Kinetic Resolution of Secondary Aryl Alcohols : Synthetic Applications and Mechanistic Studies
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The research described in this thesis focuses on the catalytic acylative kinetic resolution (KR) of aromatic secondary alcohols, using a planar-chiral 4-(dimethylamino)pyridine (DMAP) organocatalyst.In the first part of this thesis, the substrate scope of the above mentioned process was expanded to aromatic secondary alcohols that contain an extra functional group in the alkyl moiety, such as 1,2-azido alcohols, 2-hydroxy-2-aryl-ethylphosphonates and 2-hydroxy-2-aryl esters. Thus, the preparation of highly functionalized compounds in their enantiomerically pure form with excellent enantiomeric excess (up to 99% ee) was achieved. Furthermore, the synthetic applicability of this methodology was illustrated through the synthesis of two high value compounds, (R)-Pronethalol and (S)-3-hydroxy-N-methyl-3-phenylpropanamide, which is an immediate precursor of bioactive molecules such as (S)-Fluoxetine.The second part of this thesis deals with the mechanistic study of the acylative KR catalyzed by the planar-chiral DMAP derivative. Reaction Progress Kinetic Analysis methodology was used in the investigation of the reaction mechanism, probing that no notable product inhibition or decomposition of the catalyst occurs in the studied system. The reaction rate showed fractional order dependence on the concentration of both reactants. Furthermore, NMR spectroscopy was utilized to study the equilibrium between the different catalyst states, which explains the measured kinetics of the reaction.
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